Helgoland Class Battleship - Design

Design

The Triple Entente between the United Kingdom, France, and Russia had been signed in 1907. Germany had become significantly isolated—on the Continent, Germany was hemmed in by France in the west and Russia in the east, and the UK, with her powerful navy, was capable of blocking German access to the world shipping lanes. Admiral von Tirpitz reacted to this development with the request for newer and stronger capital ships. His thoughts on the matter were, "The aim which I had to keep in view ... for technical and organizing reasons as well as reasons of political finance was to build as steadily as possible." His appeal came in the form of the proposed Second Amendment to the Naval Law, which was passed on 27 March 1908.

For the second class of German dreadnoughts, there was considerable debate as to what changes would be made from the first design. In May 1906, the Reichsmarineamt (RMA, Imperial Navy Office) received word that the British were building battleships equipped with 13.5 inches (34 cm) guns. As a result, the General Navy Department advocated increasing the caliber of the main battery from 28 cm (11 in) to 30.5 cm (12.0 in). Admiral von Tirpitz was reluctant to agree to this change, as he wished to avoid escalating the arms race with Britain.

Admiral von Tirpitz's hesitation at increasing the armament of the new ships was lost when it became known in early 1907 that the United States Navy was building battleships with 30.5 cm guns. In March 1907, von Tirpitz ordered the Construction Department to prepare a design with 30.5 cm guns and 320 mm (13 in) thick belt armor. Some dispute remained over the arrangement of the main battery. The two Minas Geraes-class battleships being built for Brazil mounted the same number of guns, but in a more efficient arrangement. Superfiring turret pairs were placed on either end of the ship, with two wing turrets amidships. Admiral von Tirpitz favored adopting this arrangement for the Helgoland class, but the Construction Department felt two superfiring turrets could be easily disabled by a single hit. As a result, the hexagonal arrangement of the preceding Nassaus was retained.

The Naval Law stipulated that the lifespan of large warships was to be reduced from 25 years to 20 years; this was done in an effort to force the Reichstag to allocate funds for additional ships. The reduction necessitated the replacement of the coastal defense ships of the Siegfried and Oldenburg classes as well as the Brandenburg-class battleships. The battleships that von Tirpitz had failed to secure in the First Amendment to the Naval Law of 1906 were now approved by the Reichstag. The Naval Law also increased the naval budget by an additional 1 billion marks. After the four Sachsen-class armored frigates had been replaced by the four Nassaus, three of the Siegfried-class ships—Siegfried, Beowulf, Frithjof—and the unique coastal defense ship Oldenburg were the next slated to be replaced. The Helgoland-class ships—SMS Helgoland, SMS Ostfriesland, SMS Thüringen, and SMS Oldenburg—were ordered under the provisional names Ersatz Siegfried, Ersatz Oldenburg, Ersatz Beowulf, and Ersatz Frithjof, respectively.